Nuclear Energy has come under the spotlight after the Japanese nuclear plant disaster with people focusing on the strengths and weaknesses of nuclear power.One of the most important aspects of nuclear based power is that it is highly efficient.Nuclear Energy is currently the most efficient power source in terms of the fuel required,land area needed and also the waste it produces.The reason for this is that nuclear based electricity is primarily produced from nuclear reactions while other forms of energy like natural gas,coal and oil use chemical reactions.Other such as wind energy convert mechanical energy into useful energy.Nuclear Power currently is mostly produced through nuclear fission as nuclear fusion is still in infancy and its not certain that mankind will be able to use nuclear fusion in a safe manner to generate energy.

Energy Densities of Nuclear Energy vs Fossil Fuels

The Energy Density of Nuclear Energy compared to Fossil Fuels is very high.While most fossil fuel types have similar range of energy output per unit of mass,nuclear energy is almost a million times more efficient .The table below shows the energy densites of nuclear energy fission reactor to different types of fossil fuel

Fuel Type

Energy Density (kWh/kg)

Number of Times Denser than Coal

Nuclear Fission (100% U-235)

24,513,889

2,715,385

Natural Uranium (99.3% U-238, 0.7% U-235) in a fast breeder reactor

6,666,667

738,462

Enriched Uranium (3.5% U-235) in a light water reactor

960,000

106,338

Natural Uranium (99.3% U-238, 0.7% U-235) in a light water reactor

123,056

13,631

LPG propane

13.8

1.5

LPG butane

13.6

1.5

Gasoline

13.0

1.4

Diesel fuel/Residential heating oil

12.7

1.4

Biodiesel oil

11.7

1.3

Anthracite Coal

9.0

1.0

Water at 100 m dam height

0.0003

N/A

Source: nuclearfissionary.com

Efficiency in Terms of Nuclear Power Plants Load Factors

Nuclear Power Plants have one of the highest load factors in the power industry.Nuclear Power Plants do not suffer from fuel shortages (except exceptional cases) like thermal coal power plants (eg. India) .Nuclear power plants account for about 11 percent of America’s total electricity generation capacity, but because they operate at high levels of efficiency and reliability, they produce nearly 20 percent of the country’s annual electricity supply.U.S. nuclear power plants have performed at an average industry capacity factor of more than 87 percent for the past seven years.

Coal Power Plants and Oil Power Plants perform at 80-90% load factors while solar and wind energy power plants perform at between 15-35% depending on the energy resource and technology types.

Efficiency in Terms of Waste Generated

Nuclear Power Plants produce much lower mass of waste as compared to normal fossil fuel plants like coal,natural gas and oil.Note these fossil fuel plants produce greenhouse gases like carbon dioxide etc. besides coal produces byproducts which are highly dangerous to human health like mercury etc.There are also byproducts generated like fly ash which are also dangerous and harmful to the environment if not disposed of carefully.Nuclear Waste though is a different matter.While some can say its low in quantity the potential hazard is also of magnitudes higher.For example the whole Fukushima danger was due to the spend nuclear rods or nuclear waste.Nuclear Waste is one of the most difficult waste products to transport and store because of its dangerous radioactive effects.Given the long life of some of the transuranic elements Nuclear Waste has to be stored in a safe manner for thousands of years which is a tough given that the chances of leakage become enormous in such a long time scale.Storing of Nuclear Waste has to be performed in a extremely complicated manner which is also enormously costly.Also there are problems of NIMBY with Nuclear Waste Storage as nearby residents don’t want such toxic waste stored anywhere close especially as it does not bring any economic or social benefits.Not there is no permanent storage site despite many decades of planning and billions of dollars being spent.While Japan and Europe reprocess the fuel in the hope that they will be used again that remains a dream with thousands of tons of HLW piling up.USA does not reprocess and also has more than 60,000 tons of nuclear waste waiting for a final home.Till then most of the spent nuclear fuel is being stored in spent fuel pools and dry casks making them vulnerable just like another Fukushima

Summary

We can say that Nuclear Power is most efficient form of energy generation in terms of energy density however in case of waste it is not so.This is because disposing of nuclear waste is a very costly and complex activity which many of the developed nations have shown complete disregard for.Nuclear Power is also efficient in terms of cost (the older plants that is) and plant load factors.

Abhishek Shah

Your article is great and informative, what you failed to mention was the fossil fuel plant waste amounts. Since the Nuclear industries inception we have 60,000 tonnes of Nuclear waste, but, a typical 1000-megawatt coal burning plant emits 100,000 tons of sulfur dioxide, 75,000 tons of nitrogen oxides, and 5000 tons of fly ash into the environment per year while a typical 1000-megawatt oil-burning plant emits about 16,000 tons of sulfur dioxide and 20,000 tons of nitrogen oxides. Some of the effects of this pollution are damaging the human lungs, acid rain, and global warming from the greenhouse effect. According to scientist our world can recover from the burning of 3 gigatons of fossil fuels a year, the trouble is at present we burn 9 gigatons of fossil fuels a year!